Grate key



G. ZIEGLER Dec. 9, 1930.

GRATE KEY Filed Jan. 11, 1928 6 llllll lllllllflllflll l HUMWU IL INVENTOR George Ziegler I; in.

mM IAA/Vg/I ATTORNEY Patented Dec. 9, 1930 U N I T n ems PA T OFFICE GEORGE ZIEGLER, F BOGO'IA,. NEW JERSEY 1 GRATE KEY Application filed January 11, 1928. Serial No. 245,981.

grate, and in this manner to provide a sup port which will permit the same depth of fuel to be used throughout.

A still further object of the invention is to provide an improved form of grate key wherein the air is admitted while travelling at a substantially forty degree angle to the surface of the key. 1 In the accompanying drawing Figure 1 is a side view of a plurallty of keys embodying the invent-ion, arranged as they will appear in a complete grate.

Figure 2 is a side view of one of the grate keys shown in Figure 1, the same being on an enlarged scale.

Figure 3 is a top plan view of the grate key shown in Figure 2.

Figure 4 is a sectional view, approximately on line 4-4: of Figure 2, the same beingon an enlarged scale.

Referring to the accompanying drawing by numerals, 1 indicates a key as a whole which is supported by a bar carried by an endless chain or other member forming no part of the present invention. In travelling grates, different forms of chains, cross bars or other forms of support are provided,

whereby the various grate bars are caused to travel from one end of the furnace to the other, around the wheel and back to the starting point around the second wheel. This structure is old and well known, and forms no part of the present invention except that the various grate keys 1 are used on some kind of a support of this kind.

Each of the grate keys is provided with what may be termed a body 2 carrying hooks 3, which hooks are fitted over supporting bars or other members when the keys are in use. The body 2 is also formed with a top structure 4 integral with body- 2 and this top structure on its upper faceis provided witha plurality of parallel spaced grooves 5 for permitting thedistribution of air beneath the fuel carried by the ridge members 6. The side of the top structure 4 is pro-- vided with a plurality of inclined grooves 7 merging into the groovest'. The inclined grooves 7 are preferably substantially parallel and incline at an angle of about fortyfive degrees from the horizontal. Also, these grooves are preferably curved, though this is not essential. These grooves are preferably open wider at the bottom as indicated at 8, than at the top, thus permitting the air to freely enter and finally escape out the top and into the grooves 5, as well as directly into the bed of fuel carried by the'grate. In Figure 1, part of a complete grate is shown without the support, and from this it will be observed that the ends of the grate keys overlap and the various grooves 7 continue to function even on the overlapping portion.

In forming the top structure 4: of body 2, the upper surfaces of the ridges 6 are arranged in the same plane. Generally speaking, the upper surface is a flat plane, and when the various grate keys are properly arranged in place, a flat straight grate is presented as shown in Figure 1. This will permit the bed of coal or other fuel to be the same depth throughout and, consequently, to burn'at the same rate of speed throughout as the air is quickly supplied to the coal. Where the grate keys are individually arc-shaped, the coal bed is thicker at the point of overlapping and, consequently, will not burn as rapidly as the coal over the highest point of each grate key. By making the ridges 6 of the supporting surface of the keys in the same plane, this objection is eliminated, and by making the air passage-ways or grooves 7 inclined, the air is discharged at an angle and, consequently, thoroughly mixes with the gases so as to provide a better combustion without blowing.

What Iclaim is:

1. A grate key, comprising a body having a top structure formed with a flat face, said top structure having spaced parallel transverse grooves in its face and curved inclined grooves in one side merging into said parallel grooves, said inclined grooves extending from the top to the bottom of said top structure, the depth of said curved inclined grooves being less than half of the thickness of said top structure.

2. A grate key, comprising a body having a top structure formed on its face with grooves and on one side with curved air grooves inclined longitudinally of the 'keyi and extending from the top to the bottom of said top structure, the depth of said curved air grooves being less thanhalf of. the thickness of said top structure.

3. A one-piece'grate key comprising a body having, a top structure having spaced transversely positioned grooves in its upper surface, and unbroken curved inclined air grooves inone of its sides extending from the lower surface of said top structure to said spaced grooves, said curved grooves respectively discharging into said spaced grooves.

Signed at New York, in the county of New .York and State of New York, this 10th day of January, A. D, 1928.

. V GEORGE ZIEGLER. 

